SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9f43287705f288c2ac91970a41f8e69fe27c1aa76d7f8b3cc9e67901bc5d9986' 
  AND token = 'jWYg1G+hbg4d3CWzYKP8ysicMgpDfvPfzGsUIkFUgpQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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