SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'f651640063bf804185742d655a68c5c8a0f5cae8b12015447f46b1fcae121164' 
  AND token = 'uqtk1aohpUbJiaUm/w08KRFufZ834KE5n301TWEAvqQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00056

JSON explain

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