SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '6f882cc51e5b81aa1888f50cc0d628a115661b683e43ff6ebafb45524c011334' 
  AND token = 'ZOpVYTLb9iO2CTuI3aUVZRycZBl8V0kNWiKC+HiM67k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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