SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dd8f854cc8fbd405ccd00a83f84a8f4cafd5519c260e7d7cd9c978e830136912' 
  AND token = 'M2tdOmNbfztAXqavFihUy1ftaFcb6DecdAZI5Ng0ADc=' 
  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"
    }
  }
}