SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e9753179d30f68fd6484ad9595688548f1617436df6d04f841767427875983e1' 
  AND token = 'JNFjoidRyAwqmMdHXNUc8SRc7wDCoi+HvrKEQFP2Hxg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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