SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ff289a442b030168b9d807e7e1825bb71dc7b980272f13ba35c80ecdac1ef2f5' 
  AND token = '+jUOvzgxO9lhANmveJ7Cg8CYixqXuhxISO86ut3Yg1Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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