SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '094674f94c8a94de90a9b2d713f3bd776b49f86eb16dc0b82af9923e6a1fc1fc' 
  AND token = 'fEBRSsBJSvMq+QVW+lmsS/AMlR4lIwVgC6ihw/kxx18=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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