SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '203baacef1038992d347bcf08614dc6778727148dcc4660a811312aac6b082c5' 
  AND token = '/WZysCye3076zxu2QX1AlY/yKzSmL874h1fb8AhPXhY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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