SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '95d493c8e21a1f9d4721467fbd41515c246d80a4a26eb1d483bae9116126ca81' 
  AND token = 'X35zrCUlbLOxQm6+cm+l3wgQ7TDxhp6ziKXE/2muYSU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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