SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ce817d27d3989d25ed4a408817e02ff007a6b71d6a9c13c3981b8bf8b3d1956b' 
  AND token = 'R0dOYVuR5o4qnSjZJZBilZoeC7mCo3JbhLVfQzxLnkc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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