SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd59289b3b6a4a6d455af0f3b9ecb27c52212d6e7cb350ab4d21131133e0a7434' 
  AND token = 'qcdOeIGQTFIRN9KFGAfAI21zVYTPuSuNI+lBDta8DAY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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