SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '88758491aa8d1d57ba882e552b290409efab6b8ff2bcade2eeafb3db23b8120d' 
  AND token = 'e3EF1nlWEnpmfxxEQX1J/ELBuMvCvwxb+Yx3zRAoyDE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}