SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '58cc618aaf951bce927ae4f4b51976fdc432f9c850380ae49b63555e80eac70a' 
  AND token = 'eLV9TlEYoWGmC7RtCA0/wKrLqtnvbYY2ohILYCxe1T4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}