SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4b11309417e622b028541f46ef2e00431053eb0c03ae8c048c1c961d4b957409' 
  AND token = 'pZzDuRn6+Ikp4ir428RFMMHsIkpfGAnjT3eOlQhKIfQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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