SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '94287a9985309a315208bcf47905ef51d5fed5d4b65ef9e8a2a51c02d2bd5852' 
  AND token = 'H09EadLZN4brxfRcAW3v0MmgRwipIEjaumWdj8q/Exo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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