SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3c1a065ef83ceda12318d280263536986ef9890f90dd8123e518e8472a75bb72' 
  AND token = 'veot32aTwv6xjbPsV7tq0o3/w6GIYJf5OdgWCoEUYwo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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