SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '6ed47c1552216b7c7df1a81533bcdcb043b499f6ae9cb4412ab1c5f2136b0e3f' 
  AND token = 'LEpDJaTfvP/fX1qDF2SEnCuvvlNWHcGQzmKwjHS0hFo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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