SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2eb2c91149d584c7f5505b878d7f4d1669d966a7c82bd4061c10dcfd147e7fb1' 
  AND token = 'uQK/omFOYxflkMbGrKMbsuJJzcKsUhe+XOAV/9agX5Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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