SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4601b07f8f25b0540efb3f29673cd8f577fd1c7932feda4bdc8567fb3ca6652b' 
  AND token = 'q65dB7UF/3bV5EkSzUf/grgoirJZh+Opvc6zBuN8GXE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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