SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a41dbfa3703723ea07dde6b25d1415f186832b6d15e0b964050df80b528cf132' 
  AND token = 'vuzYsQdti5i2kGlxkaREBcEPHoZ5rZmqhiF+W3AUs1U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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