SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0ab8810831ebfaee7c5a12d82327fdc5f24776630836f92ba41bd4174a8092fd' 
  AND token = '5lUchjc3SgFGitfZwDIJyqh5n4Lmz8KCeWQr54fx0jE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}