SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd7a2ce549925e815aaee2f9055bdc7f474a1b576d1bcf49270830c4ee37b33f9' 
  AND token = 'pGPd17/rn3Iw/eJ7nQREckqym+WVPbZPPK7J5ogfFiQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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