SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '02d9c1ff504ef960ac545b0e3f829311527766c38cf8fca712eaeb62027b4cf6' 
  AND token = '7rifwy+jOKUKTnQPd0Eeg16tt6UXrriqewIM4nERGl0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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