SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b9388dfe7ffff648de714aea5d14a09ad7b1f0395e294f3299cdccbbb1d94f2e' 
  AND token = 'ViKmaScfcFrEtG3KTzWQOjb2oojs9/nwrbHS6F94INc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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