SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0ca4e0e1cb8c27e005d46e44126716a6c87f49e2947eccdc8ac0de9e7416a054' 
  AND token = 'M2HAJDxNRLQl56i1FAAF0hlauCAHbTHHtqjrZbr5P8c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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