SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '80f03a620de05b952fbaa4f074c7a25c686ca3d77a5af352a1aabcc25ed6fcb6' 
  AND token = '6WzAEJqgCYCNqNn+OlGdGxEyozJiOswo27W1pa37WII=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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