SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '07346d5239a0c315686f66448c2eaf8f9c745d5d2d982b8de5d48e47365cbb99' 
  AND token = '/Q44LU2Pqri+YkzxhLYU8dLIiIi1XMFZz1YVsiWG1Xs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00093

JSON explain

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