SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c0fb98fe7372f52d4bcf3a08b46269bfaaa8fdf9b28418c53d74ccb7618dfb45' 
  AND token = 'jA06Y/Lz9oZJUmW5WSG+KB3dS1uNUNGKMTWqUrkU8VM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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