SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a9bd1942f881007acde917511c6210c8d477e1a3c693df69cbb98f5e02901d81' 
  AND token = 'Rzsr4snotKL+YHpMJn80l9dE9nkc7muNpOEtnMDYW74=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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