SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fcda91684a238bb68ada704e0d215b24750292218cfaf121d3e79cc080d4372c' 
  AND token = 'Wn/7oHO0Zq+sd9iVVXJe38gZf6D0tL55A4pnuEREMvk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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