SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '45264097ff5f22c3e01caca1c69ed3e7bc5683a27424c0768d60c388d37df4aa' 
  AND token = '5cvhjRA1IEZObGHGS8f9XmcNKcOPIsdBqjqF5uLsNbA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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