SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0028956985765060f57901ca8181ff4f0d4006ca38b2f12c775bfcf2b34eb4cd' 
  AND token = 'yeM7PCCKiNjxV7TrDbb8lYCpH702f0ppbgw80YUG7WY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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