SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2e37a8a81453c61deb5858c5615232070a9500131e0af37c08cbb285241a2873' 
  AND token = 'm+TlSISFoawlseWa72K5KKERHjPLbsxgRe+qGQhd2Yc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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