SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '17bab1c34dbeeadbd567cbaf4df0b23a8416997484b0585c0d7294596ca38302' 
  AND token = 'opTvkpVQPHOAUlGz5NJprJrY0AforZc3RQctRdBmDqA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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