SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a112f0db4cc8b9375e7b32d64581d69b3cf6ff3345d8d91030dd9a3bc3be93de' 
  AND token = '5qDRj5/oKlJfixQfxVysxeuTmXKfFfMWnOUmhqiBwds=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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