SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '69cd41b856a05ea87726b0224e25abbf8b7364ab2956bc934c9a9a2976643ec6' 
  AND token = 'ZF4jg512jYYWwsp8wPv5SJW/ZsZcnLMMvhFsHs6/eqg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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