SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0ab1472e737f181d31c20d389edef63344e479d2423eef1fddbe31c5e0870d03' 
  AND token = 'AMA79A+V6GHXEuVWBrqZcicLCFhtfm4wLnfYFk7vlYM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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