SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e8dc5b451ee85b29407847dd1a0f8f9e69783c8269aa72d124d9ef979459d0f0' 
  AND token = 'M/pBcfaZxOei1qi9lALPpoMdCxKZq6UOu/7A6ahp3DY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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