SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '27445a1c83325394b2c4815cb8b4ba9c798cbd34221867ed49e420f0b72bd10f' 
  AND token = 'Jr0J5k3aZ3CK1FGs3ZcAKtuWQl6uRCxIcIPCDTBO0HU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}