SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c9448901ff3ce4ac5c0a782ee35ed65656ed4d611488a7e0d07c7cf5820981ad' 
  AND token = 'XCnhexOhdyMQzQDSfioW9etRYCuQsHy/3O84O/sERiQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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