SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '9541500c5bb7aaef890fd42176de975434180e1d5775f86f294df162edb3b513' 
  AND token = 'Z3SeOQ9M/5sqxFh5Ijd29B7P8OgLPf7/7/KW3N50HH0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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