SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '77b77ddc680667223690d3132da0bc8c9dfa0cde4b78e047619446f14b89228f' 
  AND token = 'G59UqjOSUm3+qPJw3A5Rm5KRFHK4QxB3NTbCWpnA4t4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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