SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4d208534a2a09fa2b4a14693f017f11752e85ceba4c2db9e5459fcb1451da30c' 
  AND token = 'fEsXiqFVR3NG4ONlMAV/tlwekG86w2n/AJCcz//6Urk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00108

JSON explain

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