SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c9a2c44f0851befb922f59eb90949665f7b6cf60326d168c61ddef707b561ecf' 
  AND token = 'iwmuVVf5gPmdCl1DZtC1PAcdLFDx/DpdR4EbLXsOBRk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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