SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aadbcde5e8130ff9346225f9b3ee6859dd0680c01167822aba931cb925e6eb84' 
  AND token = 'qJ/7pIq4QggS668t4dgAnftiEJ/tmnwm+Lc8NvthEMk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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