SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '48cb6117cd3d5551ab0220d43ef8f98488461a59971f226558e54d8ad6729ca7' 
  AND token = 'j8rvghxPZSWqqOjgDdj5Y+bOFBGBmMghufs0R1I+bSQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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